Type wheel typewriter



June 29, 1937.* HL sCHNFELDER 5 T YPE WHEEL TYPEWRITER 'Filed July 17, 1934 3 Sheets-Sheet 2 Eig. Z

'f lnventor:

Z u 29, 1937.- H. SCHONFELER 20858609 V TYPE WHEEL TYPEWRI ER Filed July 17, 1934 3 sheetsesheet 3 Patented June 29, 1937 PATENT OFFl CE TYPE TYPEWRITER Herbert I Schnfelder, Leipzig; Germany, assignor 'to Edgar Hoflmann, Leipzig Germany Application July 17, 1934, Serial No. '135,693

In Germany July 18, 1933 vs Claims (ci: 197 47) This invention relates a type wheel typewriter, in which the type wheel is turned bymeans of an adjusting lever moving over a 'letter seale 'and movable parallel to the platen and 5 a rack connected with the lever and engaging a gear coaxial with the type wheel 'for adjusting the'type to be printed, and displaced for printing towards the platen bymoving the adjusting lever and simultaneously securing the position of the adjusted type.

In known typewriters of this class the type wheel is arranged on a lever which is moved about a flxed pin for printing the type. This construction sufiers from the drawback that,

during the printing motion, the adjusting gear with which the type wheel is connected will to a slight extent roll over the rack whereby the adjustment is altered and printing unfavorably aflected. Looking of the type wheel as adjusted by inserting, during the printing motion. a tooth of a diso non-rotatably yet axially displaceably coupled with the type wheel and provided with guide teeth on its circumterence between two fixed guide tongues having sloping entering ends cannot eliminate this defect, as the point fixed by' the guide tongues'is -located not directly underneath the type to be printed and the motion or the typ' 'wheel about the fixed pin is rendered dii'iicult at least if the type wheel is prevented from lateral motion by the guide tongues and the adjustlng rack. This interference with the moving rods requires the interposition or an elastic intermediate member which iails, however, ef rectively to prevent slurring of the printing. Another flxing device 'for the adjusting lever in the form of a tooth attached i to theadjustin g and stop-leverand engaging a flxed toothed member cannot insure a secure position of the type-wheel. since the distance to the type and the'springiness o! the interposed parts render accurate fixing impossible. A typewriter whose type wheel is turned for adjusting the type to be printed and moved in looked. position towards the platen to eflect printing is known already, the wheel being advanced in guides. These guides consist, however, of aslide guided above the base plate by two members'and having its axis disposed vertically to the base plate with the type wheel arranged on the axis at a relatively large distance fro'mthe slide, 'Furthermorefi separate means are 'provided for adjusting-and printing the types. and the means for printing causes also the looking of the adjustment of the type wheel. An'arrangement of this kind cannot insure accurate adjustment and guiding of the type to be printed.

According to the invention,. the defects of the known machines are eliminated by arranging the guide .of a slide plate Carrying the type v wheel and rectilin'early movable towards the platen directly in the base plate of the machine, in which is located also a toothed member for lo'cking the type wheel in adjusted position, the teeth of said member being engaged during printing motion by a looking pin dis- 'posed on the underside of the adjusting rack.

In this way, reliable flxing' and guiding of the type wheel and a clear impression of the adjusted type will be attained by means of a greatly Simplified construction employing a re'- duced number of parts, as the possibility of displacement or rotation of the type wheel as well as elastic intermediate members or parts that could cause inaccuracies has been avoided. According to the invention, this guiding' of the type wheel is further utilized for eflecting motion of the carriage in a very simple manner.

'For this purpose, a spring-actuatedpawl is disposed on'the slide -plate carrying the type wheel so as to engage the carriage feed rack during motion or the slide plate to move the carriage for the width of one letter, and the spacing between the characters is eflected by axially turning the' adjusting lever and thus bringing a looking member connected therewith into the plane of the locldng teeth so as to strike thistoothed member and limit the travel of the slide plate in such a way that the carriage is moved but the type wheel cannot strike against the platen.

All parts of the machine disposed in front of .the carr'iage including the type wheel are enespecially as during the stroke the radial movement of the adjusting mark is not visible. The. scre'ening 'of the moving parts, the favorable ar'- rangement of the scale and visible writing 'insure a considerable increase in writing speed compared with the known adjusting lever machines, the more so as the space key does not refi latter on a Joint verticalshaft i2.

quire a change in the position of the hand or additional keys but fits perfectly into the play of motions, since a slight turning of the adjusting knob will instantly and with absolute reliability provide the desired spacing.

One form of the' invention is illustrated in the accompanying drawings, in which Figure 1 is a diagrammatic view of the machine according to the Invention with a portion of the front covering and the adiusting scale removed to show the parts of the adjusting device disposed underneath; Fig. 2, a plan after removal of the carrlageand the covering of the adjusting device; Fig. 3, a front view of the carriage; Fig. 4, an end view thereof showing the left end; Fig.

5, a detail view showing the right hand end of the carriage; and Fig. 6, a view of a modified construction of a type wheel.

Referring to'the drawings, the machine comprises the base plate l and two upright frame walls 2, 3 and the guide 4 for the carriage. In the walls 2, 3 a guide rod 5 is secured which carries a longitudinally displaceable and rotatable sleeve 1 provided with an edge-like adjusting mark 6. 5 .The sleeve 1 has two downwardly extending arms 3 to the ends of which a rack 3 is secured. The

rack 3 is in mesh with a gear ll coupled' with the type wheel III and rotatably arranged with the The shaft |2 30 is with its lower end secured in the slide plate |3 which is disposed vertically to the direction of the guide rod 5 in a guide i4 in the base plate i and subjected to the action of a spring |5 which holds the plate |3 with the gear li and the type 35 wheel lll in a front end position or always returns them to this position.

In the rack 3 a downwardly directed locking pin or toot h |6 is secured, opposite to which a toothed or notched looking plate or comb |1 is flrmly disposed in the base plate l. One of the arms 3 'of the slidable and rotatable sleeve 1 is fitted with a bush Il which accommodates an ad- Justlng lever 23. The lever 20 is rotatable and provided at its free end with a knob IS. At its inner end, the adjusting lever 20 possesses a short lever arm 2| whose free end is articulated to a locking arm 22, the free end of which is broadened and guided in a slot of the rack 9. According to the adjustment of the arm 2| of the ad- Justing lever 23, the end of the looking arm 22 roiecting from the under side of the rack 9 will be either in --the plane of the toothed looking 'plate i1 and thus limit the feed of the rack 9 by a motion of the arm 3 or the looking arm 22 will be withdrawn to such an extent that it will not interfere with the feed of the rack 9.

Parallel to the guide rod 5 a shaft 23 is dis placeably disposed in the walls 2, 3, as indicated in Fig. 2, which projects from the outside of a wall to the extent of its displacement. The shaft 23 carries the pawls 24 for moving the'ribbon spools, the pawls being pressed by a' spring, not shown, which is arranged On the shaft 23-, into the teeth of the spool feed gears 25 according to the position of the shaft. 'Ihe shaft 23 carries further a broad stop arm 23 which is struck by the shaft |2of the type wheel Il at each feed motion of the latter whereby the pawl shaft 23 is moved in one direction whereas the return of the shaft is efiected bymeans of the torsion spring, not shown. i

The carriage guide 4 is provided with stepped stops 21 for limiting the motion of the carriage in one direction and with astop 23 on' the other side u :for iimiting carriage motion-in the .other direction aosasoo as well as with adjustable lever stops, not shown, on both-front sides of the carriage. A paper guide plate 29 with feed rolls 30 and a shaft 3i is arranged in the walls 32 of the platen carriage and is pressed with the end of the roll against theroller 33 by torsion Springs, not shown. By means of the pins 34 a paper support or table 35 is secured to the walls 32 of the frame. which with its downwardly directed extension 36 rests on the rear end of the paper guide plate 29, so that the roll end of the latter together with the rolls 30 can be moved away from the platen 33 by pushing back-the paper table 35.

The carriage frame rests with a rack 31 secured to the under side thereof on a horizontal guide formed by pin-like elevations 38 of the base plate l. At each stroke of a type the carriage is moved by a pawl articulated to a lateral extension 39 of the slide plate l3 and held in position by a tension spring 4I. The pawl 40 forms with the extension 39 of the slide plate |3 a toggle lever which is spread during the feed of the plate |3 up to the moment of engagement with the rack 31 and then collapses so as to bring about the motion of the carriage.

Return. of the carriage is eifected by a pawl 42 articulated to the base plate l on the other side of the slide plate |3 and displaceably guided on a fixed hinge bolt 44 by means of the slot 43. The pawl 42 is Controlled and held in position by a tension spring 45 and a tension member 41 connected with a back space key 46, the spring 45 and the member 41 engaging a short arm 48 of the pawl, and the length of the tension member 41, which is flexible, is dimensioned so that the spring 45 will hold the pawl in the one end position of the slot 43.' When the back space key 46 is depressed, the pawl 42 is first moved 'about the hinge pin 44 to engage the rack 31 and then displaced parallel to the carriage guide as soon as engagem'ent is efiected.

The type wheel |0 can be raised and lowered on its shaft I2 and a coupling pin 49 connecting the shaft with the gear H by means of a cranked shaft 50 which is movably disposed in the wall 2 and the boss 5i of the frame of the machine and r fltted with the shift keys 52, 53. The stroke of these keys as well as that 'of the back space key 46 can be accurately regulated by means of screwgdin stop screws 54.

The walls 2, 3 of the machine frame have roofshaped tops as stated and serve for receiving the roof-shaped covering of the type adjusting and printing device. This covering consists of a front Vertical wall and an upper obliquely ascending wall 56. The Vertical wall 55 contains clearances for the shift keys 52, 53 and the back space key 46 as well as a slot, not shown, for the passage of the adiustin'giever 20'. In the inclined wall 56 a double scale 51, 58 with an interposed window 53 is provided to render' the adjusting mark 6 visible.

The oblique wall 56 is' disposed approximately vertically to the line of sight.

Better visibilityof the lines of writing will be insured by a type wheel as shown in Fig. 6 having the form of a truncated cone with the base on (top, as the line will then appear slightly above the horizontal central plane of the platen.

According to the invention, the main parts of the machine, especially the base plate, the parts of the frame and the roof-like covering, are mime from artificial materials, such as artiflcial resin, that can be formed by Dressing. To further reduce weight and noise other parts like the type aosaaoe frame, the adjustng gear, the carriage looking gear and the ribbon rolls with the transport toothing may -be produced as pressed or cast pieces from artificial materials of the kind indicated.

In order to operate the machine, the button Is is grasped with the lever 20 in its raised position and the member 22 is lifted by rotating the button. The frame formed -by the members?, 8, and 9 is now moved along the rod 5 until the index 6 is positioned in front of the character on one of the scales 51 and 58 which it is desired to print. -As the rack moves longitudinally of the rod 5, the type wheel lll is caused to rotate by the engagement of the rack 9 with the gear i i at the bottom of the type Wheel IO and the character selected is brought into alinement with its printing position in front of the platen 33. As shown in Figure 6, the normal position in elevation of the type wheel is such as to print a character (lower case) in the .upper or first row of characters. If the character to be printed lies in the second or middle row (capitals) or in the third or bottom row (numerals and punctuation marks) the appropriate key 52 or 53 is depressed to raise the type wheel on its shaft and thus to bring the desire'd character' into printing position. The button 19 is now depressed. This rocks the frame members T, 8, and 9, on the rod 5 and causes the gear ii on the type wheel shaft to move rearwardly and carry the type wheel with it so that the proper type character Strikes the ribbon and carries it against the paper on the platen '33. The type wheel is guided for rectilinear movement by the bar id. As the gear ll is thus moved, then pin IG enters between two of the teeth on the f xed comb IT so that proper alinement of the type With the place at which it is to strike is effected. Likewise, as soon as the frame starts to rock, no further sliding movement can take place along the rod 5 because of the engagement of pin [6 and comb ll As the shaft |2 is moved toward the platen it engages' the arm 26 so that the shaft 23 is rocked and this Causes the' engaged pawl 24, to rotate the ratchet 25 with which it engages so that the ribbon is fed along as is common in typewriters. Furthermore, rearward movement of the slide 13 Causes the pawl 40 to bias and thus move the rack 31 and carriage one space to the left.

1. A typewheel typewriter, comprising, in comi binationja baseplate, upright side walls on said.

v secured with its lower end in said guide plate, a

i type wheel, a gear on the lower end of said type wheel and rotatably disposed therewith on said Vertical shaft, said gear being in mesh with said rack, means for raising and lowering the type wheel, means for holding said slide plate with said gear and type wheel in front end position and returning it thereto, a lever movable parallel to the platen for turning and displaoing said type wheel to adjust and print a type, said lever being carried by one of said arms, a downwardly extending looking pin on the underside of said rack, and a toothed plate firmly arranged in said base plate, said looking pin engaging said toothed plate during the printing motionto secure said type wheel in adjusted position.

2; A type wheel typewriter according to claim 1, comprising a looking arm and means for connecting said arm with the' lever, said arm being adapted to be brought into engagement with the toothed plate by the lever to limit the travel of the slide plate and thus prevent the type wheel from striking the platen during the motion of the carriage. i

3. In a typewriter of the class having a type wheel and Operating means for the type wheel including an Operating lever mounted for sliding and swinging movement and an indicator sliding with the lever; a base, a carriage mounted to move transversely of the base, a platen supported on said carriage, and a casing at the front of the typewriter covering the type wheel and having a longitudinal sight slot wherethrough the indicator may be observed.

4-. In a typewriter of the class having a type wheel and Operating means for the type wheel including an Operating lever mounted for' sliding and swinging movement' and an indicator sliding with the lever; a base, a carriage mounted to: move transversely of the base, a platen supported on said carriage, a casing at the front of the typewriter covering the type wheel and having a longitudinal sight Slot wherethrough the indicator may be observed, and character scales on the casing extending longitudinally beside said slot.

5. In a typewriter of the type wheel class having a shaft and type wheel therein, a base, a slide bar mounted on said base to slide forwardly and backwardly thereon in a rectilinear path, said bar forming a support for the shaft and type wheel, a carriage mounted at the rear of said base to slide transversely thereof, a rack fixed to said carriage and extending longitudinally thereof. means. to actuate said bar, said type wheel having a plurality of rows of type, a Crank shaft supported from said base for rocking movement, said Crank shaft having a crank engaging the under side of the wheel, and manually operable means to rock the shaft selectively through a plurality of angles.

6. A type wheel for typewriters of the type 'wheel class including a body in the form of a truncated cone having its major base uppermost, and type characters carried on said body and extending in peripheral rows therearound.

' HERBERT SCHNFELDER. 

